Package org.eclipse.rdf4j.sail.inferencer.fc

Class SchemaCachingRDFSInferencer

  • All Implemented Interfaces:
    FederatedServiceResolverClient, NotifyingSail, Sail, StackableSail
    public class SchemaCachingRDFSInferencer
extends org.eclipse.rdf4j.sail.helpers.NotifyingSailWrapper

    The SchemaCachingRDFSInferencer is an RDFS reasoner that caches all schema (TBox) statements and calculates an inference map to quickly determine inferred statements. The reasoner can also be instantiated with a predefined schema for improved performance.

    This reasoner is not a rule based reasoner and will be up to 80x faster than the ForwardChainingRDFSInferencer, as well as being more complete.

    The sail puts no limitations on isolation level for read transactions, however all write/delete/update transactions are serializable with exclusive locks. This limits write/delete/update transactions to one transaction at a time.

    Author:
    Håvard Mikkelsen Ottestad

    • Field Detail

      • useInferredToCreateSchema

        protected volatile boolean useInferredToCreateSchema

    • Constructor Detail

      • SchemaCachingRDFSInferencer

        public SchemaCachingRDFSInferencer()
        Instantiate a new SchemaCachingRDFSInferencer

      • SchemaCachingRDFSInferencer

        public SchemaCachingRDFSInferencer​(NotifyingSail data)
        Instantiate a SchemaCachingRDFSInferencer.
        Parameters:
        data - Base sail for storing data.

      • SchemaCachingRDFSInferencer

        public SchemaCachingRDFSInferencer​(NotifyingSail data,
                                   Repository predefinedSchema)
        Instantiate a SchemaCachingRDFSInferencer with a predefined schema. The schema will be used for inference, all other schema statements added will be ignored and no schema statements can be removed. Using a predefined schema significantly improves performance.
        Parameters:
        data - Base sail for storing data.
        predefinedSchema - Repository containing the schema.

      • SchemaCachingRDFSInferencer

        public SchemaCachingRDFSInferencer​(NotifyingSail data,
                                   boolean useAllRdfsRules)
        Instantiate a SchemaCachingRDFSInferencer.
        Parameters:
        data - Base sail for storing data.
        useAllRdfsRules - Usel all RDFS rules. If set to false rule rdf4a and rdfs4b will be ignore

      • SchemaCachingRDFSInferencer

        public SchemaCachingRDFSInferencer​(NotifyingSail data,
                                   Repository predefinedSchema,
                                   boolean useAllRdfsRules)
        Instantiate a SchemaCachingRDFSInferencer with a predefined schema. The schema will be used for inference, all other schema statements added will be ignored and no schema statements can be removed. Using a predefined schema significantly improves performance.
        Parameters:
        data - Base sail for storing data.
        predefinedSchema - Repository containing the schema.
        useAllRdfsRules - Usel all RDFS rules. If set to false rule rdf4a and rdfs4b will be ignore

    • Method Detail

      • init

        public void init()
          throws SailException
        Specified by:
        init in interface Sail
        Overrides:
        init in class org.eclipse.rdf4j.sail.helpers.SailWrapper
        Throws:
        SailException

      • getValueFactory

        public org.eclipse.rdf4j.model.ValueFactory getValueFactory()
        Specified by:
        getValueFactory in interface Sail
        Overrides:
        getValueFactory in class org.eclipse.rdf4j.sail.helpers.SailWrapper

      • fastInstantiateFrom

        public static SchemaCachingRDFSInferencer fastInstantiateFrom​(SchemaCachingRDFSInferencer sailToInstantiateFrom,
                                                              NotifyingSail store)
        Instantiate a new SchemaCachingRDFSInferencer from an existing one. Fast instantiation extracts the schema lookup tables generated by the existing sail and uses them to populate the lookup tables of a new reasoner. Schema triples can not be queried in the SchemaCachingRDFSInferencer returned by this method.
        Parameters:
        sailToInstantiateFrom - The SchemaCachingRDFSInferencer to extract the lookup tables from.
        store - Base sail for storing data.
        Returns:
        inferencer

      • fastInstantiateFrom

        public static SchemaCachingRDFSInferencer fastInstantiateFrom​(SchemaCachingRDFSInferencer sailToInstantiateFrom,
                                                              NotifyingSail store,
                                                              boolean useAllRdfsRules)
        Instantiate a new SchemaCachingRDFSInferencer from an existing one. Fast instantiation extracts the schema lookup tables generated by the existing sail and uses them to populate the lookup tables of a new reasoner. Schema triples can not be queried in the SchemaCachingRDFSInferencer returned by this method.
        Parameters:
        sailToInstantiateFrom - The SchemaCachingRDFSInferencer to extract the lookup tables from.
        store - Base sail for storing data.
        useAllRdfsRules - Use all RDFS rules. If set to false rule rdf4a and rdfs4b will be ignore
        Returns:
        inferencer

      • getDefaultIsolationLevel

        public org.eclipse.rdf4j.common.transaction.IsolationLevel getDefaultIsolationLevel()
        Specified by:
        getDefaultIsolationLevel in interface Sail
        Overrides:
        getDefaultIsolationLevel in class org.eclipse.rdf4j.sail.helpers.SailWrapper

      • isAddInferredStatementsToDefaultContext

        public boolean isAddInferredStatementsToDefaultContext()

        Inferred statements can either be added to the default context or to the context that the original inserted statement has.

      • setAddInferredStatementsToDefaultContext

        public void setAddInferredStatementsToDefaultContext​(boolean addInferredStatementsToDefaultContext)

        Inferred statements can either be added to the default context or to the context that the original inserted statement has. setAddInferredStatementsToDefaultContext(true) will add all inferred statements to the default context.

        Which context a tbox statement is added to is undefined.

        Before 3.0 default value for addInferredStatementsToDefaultContext was true. From 3.0 the default value is false.

        Parameters:
        addInferredStatementsToDefaultContext -